Working As a Physicist

Question 1

What is the scientific process?

Answer 1

Ask a question
Create a suggestion (explanation) for the answer
hypothesis
Carry out a test to provide evidence

Question 2

What are the 7 SI base units?

Answer 2

Mass-kg
Length-m
time- s
current- A
temperature- kelvin
amount of substance- mol
luminous intensity- cd (candela)

Question 3

What is the independent variable?

Answer 3

The variable you change

Question 4

What is the dependent variable?

Answer 4

The variable you measure

Question 5

What are the control variables?

Answer 5

Variables that must stay the same

Question 6

What is absolute uncertainty?

Answer 6

the total uncertainty for a measurement

Question 7

What is the percentage uncertainty?

Answer 7

The uncertainty as a percentage of the measurement.
uncertainty/ measurement taken x 100

Question 8

How can you reduce the percentage uncertainty?

Answer 8

Measuring larger values

Question 9

What is the smallest uncertainty you can have?

Answer 9

The uncertainty caused by the resolution of the equipment

(+ or - 1/2 of the resolution of equipment)

Question 10

How do you calculate the uncertainty of a mean?

Answer 10

The mean value - the value of largest difference
Or
Half the range / the mean

Question 11

How do you combine uncertainties when adding or subtracting data?

Answer 11

You add the uncertainty of the pieces of data together

Question 12

How do you combine the uncertainty when multiplying or dividing data?

Answer 12

You add the PERCENTAGE uncertainties of the pieces of data together

Question 13

How do you combine the uncertainties when raising to a power?

Answer 13

Multiply the PERCENTAGE uncertainty by the power

Question 14

What is precision?

Answer 14

When the spread of the data is small

Question 15

What is accuracy?

Answer 15

When the result is close the the true value

Question 16

What are systematic errors?

Answer 16

Errors that shift all of the results by the same value.

Question 17

What causes systematic errors?

Answer 17

The equipment not being set up properly or being faulty

Question 18

What are random errors?

Answer 18

Errors where the results vary from test to test

Question 19

What causes random errors?

Answer 19

Changes to the control variable or the way that you measure the data

Question 20

How do you prevent random errors?

Answer 20

More repeats
Using an apparatus with better resolution
Use a computer/ data logger

Question 21

What is uncertainty?

Answer 21

The interval in which the true value lies within

Question 22

How to improve the validity of results?

Answer 22

Control more variables
Use more precise measuring equipment
Obtain more results

Question 23

How to reduce systematic errors

Answer 23

Calibrating equipment
Read results at eye level to remove parallax error